title: Characterization of the components of meleumycin by liquid chromatography with photo-diode array detection and electrospray ionization tandem mass spectrometry.
abstract: Reversed-phase liquid chromatography coupled with photo-diode array (PDA) detection and electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to characterize the components of meleumycin, a 16-membered macrolide antibiotic produced by fermentation. In total 31 components were characterized in commercial samples, including 12 impurities that had never been reported before and 12 others that were partially characterized. The structures of these unknown compounds were deduced by comparison of their fragmentation patterns with those of known components. Their ultraviolet spectra and chromatographic behavior were used to confirm the proposed structures: e.g. λmax shift from 232 nm to 282 nm would indicate the presence of an α-, β-, γ-, δ-unsaturated ketone instead of a normal α-, β-, γ-, δ-unsaturated alcohol in the 16-membered ring of the examined components. Compared to other methods, this LC/MS(n) method is particularly advantageous to characterize minor components at trace levels in multi-components antibiotics, in terms of sensitivity and efficiency.
authors.affiliation: Department of Antibiotics, National Institutes for Food and Drug Control, Beijing 100050, PR China.
authors.forename: Ming-Juan
authors.initials: MJ
authors.lastname: Wang
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Li
authors.forename: Chang-Qin
authors.initials: CQ
authors.lastname: Hu
authors.forename: Jos
authors.initials: J
authors.lastname: Hoogmartens
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schepdael
authors.forename: Erwin
authors.initials: E
authors.lastname: Adams
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents
keywords: Component identification; Liquid chromatography–mass spectrometry; Macrolide antibiotic; Meleumycin; Photo-diode array detection